The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 07, 1992
Filed:
Sep. 19, 1989
Craig S Lage, Puyallup, WA (US);
James E Small, Puyallup, WA (US);
Bamdad Bastani, Danville, CA (US);
National Semiconductor Corporation, Santa Clara, CA (US);
Abstract
A method of making complementary vertical bipolar transistors and complementary field effect transistors on the same substrate is described. The process includes forming buried layers in a semiconductor substrate which are spaced apart in a self-aligned manner by use of a lateral etching technique to undercut the mask used for definition of the buried layers. In the process, the collector and base contacts of the bipolar devices and the corresponding conductivity-type sources and drains of the field effect transistors are combined to minimize processing steps. The process also includes a silicided polycrystalline silicon layer used to form resistors and contact the various transistors.